The invention relates to screw compressors and, more particularly, to a discharge porting design of a screw compressor which enhances flow efficiency and provides for recovery of kinetic energy generated in discharge flow from the compressor.
In a conventional compressor having multiple rotors, as the rotors rotate, gas is compressed in rotating pockets. Typically, pressure ratio or volume ratio (VI) is the same for discharge porting in both radial and axial directions. This results in over-compression of some gas, and further results in inefficient operation of the compressor due to dynamic losses and loss of kinetic energy imparted to the gaseous stream, particularly for a high tip speed machine.
It is clear that the need remains for enhanced efficiency in converting kinetic energy generated by the compressor to pressure.
It is therefore the primary object of the present invention to provide improvements in discharge porting for the compressor which recover kinetic energy or dynamic losses as desired.
Other objects and advantages of the present invention will appear hereinbelow.
In accordance with the present invention, the foregoing objects and advantages have been readily attained.
According to the invention, a screw compressor is provided, which comprises a housing having a discharge port; a plurality of rotors comprising at least one male rotor and at least one female rotor rotatably disposed in said housing for generating a discharge flow through said discharge port, said discharge port having a radial portion and an axial portion, wherein said discharge port is positioned relative to said plurality of rotors so that said radial portion opens prior to said axial portion whereby kinetic energy in said discharge flow can be recovered.